Phytomyza nervosa Loew, 1869

Lonsdale, Owen, 2021, Manual of North American Agromyzidae (Diptera, Schizophora), with revision of the fauna of the " Delmarva " states, ZooKeys 1051, pp. 1-481 : 1

Phytomyza nervosa Loew

Figs 133 , 808-810

Phytomyza nervosa Loew, 1869: 52. Frick 1959: 432; Spencer and Steyskal 1986b: 181.

Description

(Fig. 133 ). Wing length 2.2-2.5 mm (♂), 2.7-2.8 mm (♀). Vein dm-m absent. Eye height divided by gena height: 2.1-2.2. Buccal cavity relatively broad with epistoma produced. Ring around eye prominent. Palpus short and broadly ovate.

Chaetotaxy: Two ori; two ors. Acrostichal setulae absent. Four dorsocentrals, decreasing in length anteriorly.

Colouration: Head dark yellow with posterolateral margin of frons lateral to base of inner vertical, large round spot around tubercle and back of head above foramen (excluding margin) brown; palpus, clypeus and first flagellomere black. Notum dark brown with grey pruinosity, and postpronotum, notopleuron and supra-alar spot yellow. Pleuron dark yellow with brown/grey mottling (paler posterodorsally on katepisternum and medially on anepisternum). Halter white. Calypter dusky with hairs brown to golden. Coxae and femora yellow with light dorsal mottling on fore femur (sometimes restricted to base) and with brownish dorsal spot near base of mid femur and near apices of mid and hind femora; tibiae brownish; tarsi brown. Abdomen brown with male sternite 8 and posterior margin of tergites 5 and 6 yellow.

Genitalia: (Figs 808-810 ) Hypandrium subtriangular with apex rounded, and with long, separate basomedial plate; inner lobe transverse, arched and with several anterior setae. Postgonite long and flat with apex broad and emarginate apically. Halves of basiphallus narrow, diverging apically. Hypophallus broad and U-shaped, above one pair of converging narrow bars that nearly meet to form a triangle. Paraphalli small, weakly sclerotised, converging apically, but not meeting. Mesophallus length 2 × width, narrowing apically, rounded basally; duct adjoining mesophallus pigmented. Distiphallus divided into one pair of very narrow, slender, ventrally pointing rods slightly shorter than mesophallus. Ejaculatory apodeme short and finger-like with swollen base.

Host.

Unknown.

Distribution.

USA: DC, IA, IL*, IN, KS, MD*, MI, PA, TN*, VA*.

Type material.

Holotype: USA. District of Columbia (1♀, MCZ; type No. 13432). [Not examined]

Material examined.

USA. IL: Chicago , Thatcher Road , 29.v.1949, A.L. Melander (1♀, USNM), MD: Cabin John Bridge, 28.iv.1912, Malloch (1♂, USNM), nr. Plummers Id., 25.iv.1915, R.C. Shannon (2♀, USNM), Montgomery Co., Plummers Island , 38°58'N, 77°10'W, Malaise trap, 24.iv-7.v.2006, D.R. Smith and J.W. Brown (1♀, USNM), 25.iv.1987 (1♂ 1♀, USNM), 4mi SW of Ashton, G.F. and J.F. Hevel, 29.iv.1984 (2♀, USNM), TN: Cocke Co. , Ramsey's Cascade , 8.5mi E Gatlinburg, Great Smokey Mountain National Park , 35°42.2'N, 83°21.5'W, 1900', 28.v.1999, S.D. Gaimari (1♀, USNM), VA: Chain Bridge, 20.iv.1924, J.R. Malloch (1♂, USNM) .

Comments.

The broadly ovate palpus is characteristic of this species, as is the bright head, prominent parafacial, lack of acrostichal setulae and large body size.

Figures

Figures 131 - 138. 131 Phytomyza (Napomyza) lateralis Fallen, female and puparium 132 Phytomyza compta (Spencer), male holotype, lateral 133 Phytomyza nervosa Loew, lateral, with detail of proclinate orbital setulae (arrow) 134 Phytomyza crassiseta Zetterstedt, female (D. Cheung - Ontario) 135 Phytomyza sp., female (S. A. Marshall - Hornings Mills) 136 Phytomyza sp., female (B. Dupree - Georgia, Atlanta) 137 Phytomyza sp., female (K. Hall - Washington, Lacey) 138 Phytomyza bicolor Coquillett, female on Caltha palustris (S. A. Marshall - Ontario, Spring Creek).

Figures 805 - 810. Phytomyza loewii Hendel, male genitalia 805 hypandrium and postgonite, ventral 806 hypandrial complex, left lateral 807 phallus, ventral 808 - 810 P. nervosa Loew, male genitalia 808 hypandrium and postgonite, ventral 809 hypandrial complex, left lateral 810 phallus, ventral.